Die casting machine



Feb. 21, 1933.

w. MfLESTER 1,898,671

DIE CASTING MACHINE Filed Sept. 8, 1931 3 Sheets-Sheet I Feb. 21, 1933.

W. M. LESTER DIECASTING MACHINE- Filed Sept. 8, 1951 3 S eets-Sheet 2 W) W/(este Feb. 21, 1933.

W. M. LESTER DIE CASTING MACHINE Filed Sept. 8, .1931 3 Shets-Sheet 3 liw/ezh 7/771 Zeser Patented Feb. 21, 1933 1,898,671

UNITED STATES PATENT OFFICE WIPLIAM 1L LESTER, F SHAKER HEIGHTS, OHIO DIE CASTING MLaOHINE Application filed September 8, 1931. Serial No. 561,676.

The principal objects of this invention are vent excessive oxidation of the molten metal. to provide a reservoir for molten metal mov- It is provided with an opening 14 for a purable from the melting pot in position to have pose to be described. the metal forced therefrom by a plunger into On the base is mounted in ways a slide 15 5 the die; to provide means for filling said adapted to be adjusted by a screw 16 and reservoir by'immersing it in the melting pot; hand wheel 17. This slide is provided with to provide a pair of elements holding the said two transverse pins or shafts 18 and 19 which reservoir between them and means for lowconstitute pivots. Pivoted on the shaft 19 ering them, with the reservoir, into the meltis an upri ht frame end 20. Supportedby ing pot so that the reservoir can be projected links 21, pivoted on the shaft 18 is a movable between them into the molten metal for filldie plate 22 pivoted to the links 21 by a cross ing; to provide a motion for the casting apshaft 23. Through the end frame 20 and the paratus to accomplish the last-named object; die plate 22 pass four rods24 securely fixed to provide a construction in which the gate to the frame 20 but the die plate 22 is slidable will be sheared off by the motion of a reseron them.' The frame of which the casting voir toward the melting pot; to provide a machine is made up consists of the end frame construction for removing the surplus metal 20, the rods 24 and another end plate 49. The with the gate, following the casting operaplate 49 has an extension carryinga cylintion, and to provide simple means for closing 1 1' 44:. The parts 20, 24, 49 and 44 constithe die and holding it lo d, tute a rigid frame after the bolts on the rods Other objects and advantag of th i 24 are tightened. This frame is pivoted to vention will appear hereinafter. swing about the axis 19. These rods are pro Reference is to b had to th o yvided with springs 25 against which is 10- 25 in drawings, in which cated a front die-plate 26. These springs Fig. 1 is a central longitudinal sectional Press the ie Plate away from the end frame view of a die casting machine, showing a pre- Supported 011 this 1 Plate is 011%, ie ferred embodiment of thi i ti member 27 and the other die member 28 is Fig. 2 is a plan of th same; connected with the die plate 22 by a support Fig. 3 is a horizontal sectional view of the same with the die open; The die plate 22 is moved along the rods 24 Fig. 4 is a section l i f th lti by the action of a P1St011 30 1n a cylinder 31. pot, simila to Fig. 1, ho i th reseryoir O 1l1s admitted behlnd this piston to force the and a part of the machine lowered into the d1eplate 22 foliward f afterwards it is 35 metal in th lti pot, d moved back by oil admitted on the front side Fig. 5 is a sectional view similar to Fig. 1 of the p The Plstoh rod 32 Pastes showin a difi ti through a packing nut and guide 33 and is The machine is designed with a base 10 f l h y Secured to a double rack which h i a t on hi h th ltin furnace in turn is secured to aslide 3f sliding in ways 40 11 is located containing the melting pot 12. 36 9 the Plate 22 9 guide The P The furnace can be of such construction as to Poslte Packs 34 Flesh Wlth Plvoted Segments burn any kind of liquid or solid fuel. The hy lmkS Operate links 37 to machine is adapted to cast any non-ferrous frce the die 28 against the die 27 and hold metal or alloy having melting points at or the (116 45 below that of brass. If alloys having melt- Assumlng the dle t0 be held g her in ing temperatures above 1300 Fah nh it are this way, oil is admitted to a'. cylinder 44 to be melted,or those requiring minimum conbehind the P Il The piston rod 46 is tamination with iron, .the melting pot can connected through adouble plate connector be made of graphite instead of iron, or any 47 with a plunger 48. This connection. is

gsimilancrueible, restin on four legs. The made by col ared eads on the rod 46 and melting pot s covered y a plate 13 to preplunger 48. This plunger passes through the end plate 49 and into a horizontal metal reservoir 50 which it fits perfectly and it forces all of the metal out of that reservoir into the die. Then the piston 45 is withdrawn by 5 forcing oil in at the other side of the cylinder. Thus the casting operation is com- .pleted.

This casting is performed under high pres sure. Oil is now admitted, as stated, to the rod end of the cylinder 31 and it is also admitted to the head end of a cylinder 51. Since the reservoir 50 is very tightly wedged by the piston 30 between the two plates 26 and 49 the piston will not operate until the locking tension in the link mechanism for opening the die has been relieved. By means of a sliding bearing 52 for the link pin con necting link 37 and the movable die plate 22 the locking tension is relieved before the die starts to open. The piston 55 with its piston rod 56 in the cylinder 51 is then released and the pressure behind it forces the reservoir downwardly. The rod 56 andreservoir 50 are connected by a. connector 57 like the one 47.

The system of links at the left will gradually open the die. The mechanism is so designed as to cause the cross head link 40 carried by the links 39 to approach the half of the die fastened to the plate 22 before the full die opening has been secured. This link 40 carries bumper pins 41 for operating an ejector plate 42 carrying ejector pins 43. The opening of the die causes the ejector pins to eject the casting as the die opens.

Furthermore as the die opens, the machine frame and melting pot are moved relatively toward each other. Preferably this is accomplished by dropping the machine frame by the link 21 which is rigidly held in the slide 15 by the shaft 19 so as to swing about this shaft as the die plate moves on the opening stroke. The whole frame 20, 24 and 22 swings as a unit about the shaft 19'so as to lower the two plates 26 and 49, both secured to the rods 24.

The metal reservoir 50 is: clamped between the plates 26 and 49 until the pressure is released. Then the pressure of the springs 25 only applies. Now the pressure of the oil on the piston 55 forces the reservoir 50 down between the plates 26 and 49 to shear the surnext upward stroke, produced by the intro-,

duction of oil under pressure on the rod side of the piston 55, the reservoir will first pull up into the space between these two plates and then, by the action of the piston 30, the plates will be raised as the frame moves back to the horizontal position shown. Of course everything supported by the frame moves with the frame.

The parts are now in position for oil to be again admitted in the cylinder 31 on the outer end of the piston and for the locking pressure to again seal the ends of the reserpressing back of this dam 58. The cylinder 44 must have sufiicient stroke to permit the piston 48 to enter the cover half 60 of the die. This plunger is now withdrawn and the die opened by the link, cylinder, and mechanism previously described. The metal cylinder will be lowered and the reservoir dipped simultaneously as shown in Fig. 4. The operation is the same as in the other case.

It will be seen therefore that this reservoir 50, which is designed to hold just the amount of metal necessary to fill the die, is located in position'for the metal to be forced out of it into the die and is properly held by positive pressure during the casting operation and then released and afterwards held only by spring pressure while it is lowered. It shears off the gate when moving down toward the melting pot.

Although I have illustrated and described only two forms of the invention, I am aware of the fact that modifications can be made therein by any person skilled in the art without departing from the scope of the invention as expressed in the claims. Therefore, I do not wish to be limited to all the details of construction herein shown and described, but what I do claim is 1. In a casting machine, the combination with a melting pot, of a mold located substantially above the melting pot, a reservoir adapted to register with the mold, a plunger adapted to enter the reservoir and force the metal out of it into the mold, and means for moving the reservoir from casting position whereby the frame comprising the die plate and end piece are movable downwardly together into the melting pot, a reservoir for metal located between the die plate and the end plate, and means for moving the reservoir intothe melting pot with the die plate and end plate and beyond the bottom thereof to fill the reservoir with molten metal in the melting pot and for moving the reservoir back up between said two plates into a position for casting.

8. In a casting machine, the combination of a frame comprising a pair of opposite end plates, one being pivotally mounted, a die plate carried by the frame for supporting the mold, a reservoir mounted between one of the end plates and the die plate, means for mov-' ing the reservoir between said plate out of and into a melting pot to fill the reservoir with metal and bring it to a position for easting, positive means for holding the die plate against the reservoir and that against the end plate to secure the reservoir in position, and yielding means for holding the die plate against the reservoir when the positive means is inoperative.

4. In a casting machine, the combination of a frame comprising a pair of opposite end plates, one being pivotally mounted, a die plate carried by the frame for supporting the mold, a reservoir mounted between one of the end plates and the die plate, means for moving the reservoir up and down between said plates out of and into a meltingpot to fill the reservoir with metal and bring it to a'p0si-, tion for casting, positive means for holding the die plate against the reservoir and that against the endplate to secure the reservoir in position, and yielding means for holding the die plate against the reservoir when the positive means is withdrawn, a hydraulic piston connected with the reservoir for moving it, whereby, when the liquid is turned on to move the piston and reservoir, the reservoir will not move until the positive pressure is released from the reservoir so as to permit it to be moved by the piston.

5. In a casting machlne, the combination of a frame for supportin the dies, a reservoir movable into and onto registration with the dies and carrying a charge of metal therein, a piston and cylinder carried by the frame for closing the dies rigidly and holding the reservoir in casting position, a second piston and cylinder carried by the frame for forcingxthe metal out of the reservoir into the dies, '9. fpiston and cylinder carried by the frame or moving the reservoir into casting position'and also into a position to receive a char e of molten metal.

6. In a die casting machine, the combination of a'separable mold, a melting pot, a reservoir movable from said melting pot to a point ofregistry with said mold, and. a plunger insertable in said reservoir andsaid mold and said plunger to a position of immersion in said melting pot.

In testimony whereof I have hereunto fixed my signature,

\VILLIAM M. LESTER. 

